Electroluminescent display panels (ELDs) offer several advantages over older display technologies such as cathode ray tubes (CRTs) and liquid crystal displays (LCDs). Compared with CRTs, ELDs require less power, provide a larger viewing angle, and are much thinner. Compared with LCDs, ELDs have a larger viewing angle, brighter display, do not require auxiliary lighting, and can have a larger display area.
FIG. 1 shows a typical prior art ELD. The ELD has a glass panel 2, a plurality of transparent electrodes 4, a first layer of a dielectric 16, a phosphor layer 18, a second dielectric layer 20, and a plurality of metal electrodes 22 perpendicular to the transparent electrodes 4. The transparent electrodes 4 are typically indium-tin oxide (ITO) and the metal electrodes 22 are typically Al. The dielectric layers 16, 20 act as capacitors to protect the phosphor layer 18 from excessive currents. When an electrical potential, such as about 200 V, is applied between the transparent electrodes 4 and the metal electrodes 22, electrons tunnel from one of the interfaces between the dielectric layers 16, 20 and the phosphor layer 18 into the phosphor layer where they are rapidly accelerated. The phosphor layer 18 typically comprises ZnS doped with Mn. Electrons entering the phosphor layer 18 excite the Mn and the Mn emits photons. The photons pass through the first dielectric layer 16, the transparent electrodes 4, and the glass panel 2 to form a visible image.
Although current ELDs are satisfactory for some applications, more advanced applications require brighter displays, larger displays, or smaller displays. These applications require electrodes with lower resistances than available in current ELDs. The limiting factor in current ELDs is the high resistance, about 10 ohms/square (.OMEGA./.quadrature.), of transparent electrodes made from ITO. Therefore, what is needed in the industry are lower resistance transparent electrodes for ELDs.